Answer: (13.4996, 32.5004)
Step-by-step explanation:
The confidence interval for mean difference is given by :-
,
where = sample mean difference .
= critical t value (two-tailed)
SE= Standard error.
Given :
SE= 4.2
Now, the confidence interval for mean difference will be :-
Hence, the required confidence interval : (13.4996, 32.5004)
= -1.6
= -11.625
= -0.81818...
= 2.4814
Answer:
The 99% confidence interval estimate of the percentage of girls born is (74.37%, 85.63%).
Usually, 50% of the babies are girls. This confidence interval gives values considerably higher than that, so the method to increase the probability of conceiving a girl appears to be very effective.
Step-by-step explanation:
Confidence Interval for the proportion:
In a sample with a number n of people surveyed with a probability of a success of , and a confidence level of
, we have the following confidence interval of proportions.
In which
z is the zscore that has a pvalue of .
For this problem, we have that:
99% confidence level
So , z is the value of Z that has a pvalue of
, so
.
The lower limit of this interval is:
The upper limit of this interval is:
For the percentage:
Multiplying the proportions by 100.
The 99% confidence interval estimate of the percentage of girls born is (74.37%, 85.63%).
Usually, 50% of the babies are girls. This confidence interval gives values considerably higher than that, so the method to increase the probability of conceiving a girl appears to be very effective.
Answer:
(3) Diagonals are perpendicular
Step-by-step explanation:
